The standard reduction potentials, Eo for the half reactions are:
Zn2+ + 2e- → Zn ; Eo = -0.76 V
Fe2+ + 2e- → Fe ; Eo = -0.41 V
What is the standard emf of the cell involving the following reaction?
Fe2+ + Zn → Zn2+ + Fe
Answer & explanation
Correct answer: option 3
E0cell = E0Fe2+/Fe - E0Zn2+/Zn
= -0.41 - (-0.76) = -0.41 + 0.76 = 0.35 V